1. Field of the Invention
The present invention relates to a hermetic reciprocating compressor, and more particularly to a noise suppressing apparatus for a hermetic reciprocating compressor which can obtain high efficiency by reducing noise generating from lower shell and by preventing heat from being transmitted a suction muffler during suction.
2. Description of the Prior Art
Referring to FIGS. 1 and 2, there is shown a conventional hermetic reciprocating compressor. As illustrated in the drawing, the hermetic reciprocating compressor includes a hermetic container 3 having a lower shell 1 and an upper shell 2 integrally formed with the lower shell 1. A frame 4 is disposed in inner space defined between the lower and upper shells 1 and 2 and secured to the lower shell 1 at its opposite ends. A driving motor part 5 is mounted below the frame 4, and a compressing part 6 is mounted on the frame 4.
The driving motor part 5 comprises a crank shaft 7 rotatably supported in a center position of the frame 4, a rotor 8 secured to the crank Shaft 7 and a stator 9 supported on a lower surface of the frame 4. The compressing part 6 comprises a cylinder 10 supported on an upper surface of the frame 4 and a piston 11 operatively connected at its outer end to the crank shaft 7 via a slider 19 and reciprocating in the cylinder 10.
The crank shaft 7 is provided at its lower end with a propeller 14 which is adapted to supply upwardly cooling oil 12 reserved in the lower shell 1 through an inner hole 7a formed in the crank shaft 7.
The lower shell 1 is also provided at its suitable wall with a suction pipe 15. The cylinder 10 is coupled at its rear end to a head with a suction valve 16, a valve seat 17 and an exhaust valve 18 interposed therebetween. In the drawing, numeral 20 denotes a spring.
In operation of the above-described hermetic compressor, upon being applied with electric power, the crank shaft 7 is rotated by induction magnetic action between the rotor 8 and the stator 9 which comprise the driving motor part 5. As the crank shaft 7 is rotated, the piston 11 is linearly reciprocated within the cylinder 10 according to the principle of scotch yoke so that refrigerant is sucked in, compressed and discharged repeatedly.
That is, the refrigerant is sucked in the cylinder 10 through a suction muffler 21 (see FIG. 2) and then compressed by the piston 11. The compressed refrigerant is discharged through an exhaust muffler 22 (see FIG. 2).
As the crank shaft 7 is rotated, the propeller 14 provided at the lower end of the crank shaft 7 is rotated so that the cooling oil 12 contained in the lower shell 1 is raised along the inner hole 7a of the crank shaft 7 and supplied to the compressing part 6.
In the conventional hermetic reciprocating compressor, since suction gas is fully filled in the inner space defined by the upper and tower shells 2 and 1 and then sucked in, and a flowing path along which refrigerant gas is sucked and discharged is too long, the gas may be overheated. For this reason, the gas is increased in specific volume and lowered in density, thereby decreasing heat efficiency.
For this reason, the structure of the integral head cover 13 as shown in FIG. 2 was modified into a structure as shown in FIG. 3 wherein the integral head cover 13 is divided into a separated head cover 13' and a separated suction muffler 21' and a suction pipe is connected to the suction muffler 21'. However, the modified structure is also not suitable to a low noise structure.